Electrical switch



Aug. 24, 1954 A. H. MIDGLEY 2,687,459 ELECTRICAL SWITCH Filed May 9,1952 o /90 I3 C f' J6 Humm L16 g .fill

Patented Aug. 24, 1954 UNITED STATES PATENT OFFICE 2,687,459 ELECTRICALSWITCH Albert Henry Midgley, Moor Park, Northwood, England, assignor ofone-half to Albert Morrell Midgiey, Moor Park, Northwood, EnglandApplication May 9, 1952, Serial No. 286,967

Claims priority, application Great Britain May 21, 1951 2 Claims.

side of the slot corresponding to the non-lengthened strip. The latterarrangement will give its resulting change of length, causes a furthercontact operation re-connecting the heating circuit. i

Such switches may be used, for example, in connection with flashingsignals for indicating that a motor vehicle is about to turn.

rIhe invention further consists of an electric switch of the kindmentioned in which the sheet of spring material controls the opening andclosing of at least two circuits.

Preferably, the additional circuit is one which An embodiment of theinvention will be described with reference to the accompanying drawings.

Figure 1 is a plan View.

Figure 2 is a section on the line 2-2 of Figure 4.

Figure 3 is a section on the line 3-3 oi Figure 5.

Figure 4 is a section on the line 4 4 of Fig ure 2, and

Figure 5 is a section on the line 5 5 of Figure 1.

In the embodiment there are mounted on a circular disc I of insulatingmaterial, three terminal members 2, 3 and 4 which extend through thedisc to which they are secured by bending ing secured together by twohollow rivets I0 extending therethrough with an insulating collar itaround the head of each.

`An insulating former II is held in position by two limbs Ila whichextend through the hollow rivets I 0.

which the spring sheet 9 rests), carries a springloaded screw I2extending through a tongue 6a bent away from the spring sheet. The otherextension piece 5 of the terminal 2 carries a contact member 5a on itsinner side facing the end of the screw.

It is also formed with two upwardly turned s 5b and 5c and a screw "I isin threaded engagement through the arm 5c and with its end abuttingagainst the arm 5b.

The spring sheet 9 is rmly supported at one art 9a leaving a strip 9bseparated from the A stretched Wire I3 lies generally over the slot andis secured at one end to a bent-over ear I4a on a T-piece I4 tted in oneend of the spring sheet 9 which end is slotted to hold the T-piece.

The wire is formed through a bead 5b in a hole in the arm 5b and afterbeing wound around the insulating former II is returned to the ear 5c onthe arm 5c.

The end of the spring sheet 9 remote from the end to which the wire I3is secured, is bent to bias the unsupported strip 9b so that contactpiece 9d therein is in contact with the contact member 5a on theextension piece 5 before the wire is tightened in which position thecircuit through the Wire I3.

The spring sheet 9 is also formed with a tongue 9d parallel to the strip9b, and which is bent adjacent its free end first at right angles awayfrom the side of the sheet in which the with the sheet again.

A further extension piece I5 is secured to the disc by the terminal 4 toextend at right angles to the tongue 9d and to come to lie with its freeend adjacent the free end of the tongue and between the tongue and therest of the spring sheet of which the tongue forms part and contactpieces it, Il are provided at the free ends of the tongue and furtherstrip on the sides facing each other.

The contacts I6, Il of the tongue 9d and strip i5 respectively willalternately open and close a circuit extending from the two terminals 3and il, connected respectively to the spring sheet 9, and the strip l5,which circuit does not pass through the wire I3.

This circuit is conveniently used for hashing, say, a warning lightinside a car while the circuit which includes the wire is flashinga'turning signal light on the outside of the car.

When the wire I3 is tightened up, by means of the screw 'i extendingbetween the two frames in said other extension piece, the unsupportedstrip 9b will be snapped over into contact with the end of thespring-loaded screw i2 in which position the circuit between the twoterminals 2 and 3 extends through the wire I3.

Adjustment of the spring-loaded screw l2 will control the rate ofinterruption of the circuit between the terminals and through the wireand adjustment of the other screw 1 will control the relation of theperiods during which the circuit is made and the periods during which itis broken.

It will be understood that the supported part ci the spring sheet neednot be a continuous strip in which case the lengthening of theunsupported part would be eiected after the riveting in position.

Various other modiiications may be made within the scope of theinvention.

I claim:

l. An electric interrupter switch comprising a pair of terminal members,a sheet of spring material firmly supported at one part between theterminal members leaving a strip separated from the supported part by aslot, the length of which strip is increased slightly in relation to thesupported part, an insulating layer between one terminal member, and thesheet of spring material, a stop member on the other terminal member andlocated opposite the centre part of the strip, a stretched wire securedat one end to one end oi the sheet of spring material and at the otherend to said one of the terminal members and adapted when cold to forcethe centre part of the strip into contact with said stop member tocomplete a circuit between said terminal members through the wire, andwhen hot to allow the centre part of the strip to move away from saidcontact member and thereby interrupting said circuit through the wire.

2. An electric interrupter switch as claimed in claim 1, comprising athird terminal member and a tongue on the sheet of spring materialadapted to contact said terminal member in one position of the strip andto be separated therefrom in the other position of the strip.

References Cited in the le of this patent UNITED STATES PATENTS

